The phrase “nature versus nurture” was coined in the mid-19th century by the English scientist Francis Galton and symbolizes the debate over the relative importance of inherited factors and the environment (or upbringing) in determining the behavior of offspring. The issue has been complicated by the discovery of “epigenetic” effects, by which especially mothers can alter the genetic material they pass on to their young. A further twist to the story is provided by the finding that female birds can affect their chicks by adding varying amounts of hormones to the eggs. And a recent study has revealed that the social environment of mother quails has a direct influence on the growth and the behaviour of their young.